A large section of rock on the grounds of the Berks County Heritage Center in the Reading Pennsylvania area. I want to say this is some form of Granite but I am not a rock expert and Google is not being helpful at the moment.

Technical details:
Busch Pressman Model D 4x5 LF press camera.
150mm Caltar-S II F 5.6 lens in Copal BT shutter.
Kodak Ektascan BR/A single-sided X-Ray film.
1/15 second @ F32.
Semi-stand development in Rodinal 1:100 for 15 minutes in Mod54 daylight tank.
Scanned with Epson V600.
Cropped in post.